Safety tie rod



April 19, 1932. F. c. CRAWFORD SAFETY TIE ROD Filed April 11. 1927 VE :1.E\ jjic/K C. C'mw/b/t/ 1:1

I Patented Apr. 19, 1932 V UNITED STATES PATENT orrlca A CORPORATION 01'OHIO FREDERICK G. CRAWFORD, OI DETROIT, MICHIGAN, ASSIGNOB TO 'I'HOKPSONPRODUCTS,

INC, CLEVELAND, OHIO,

mm TIER/OD Application 111m April 11,

This invention relates to ball joint connections for the ends of tierods and drag links such as are used in the steering mechanisms ofautomotive vehicles.

The general object of this invention is to provide a ball jointconnection construction that is safe, strong, and durable, combined witha structure readily assembled and serviced, suitable for economicalmanufacture, 10 and in which looseness and rattling of the joint isprevented.

It is another object of this invention to provide a. ball jointconnection wherein the ball is inserted from the bottom and a cover 16secured thereover so that even if the bearin for the ball come loose oractually fall out, the tie rod or drag link cannot become detached fromthe ball, this being an important safety feature as a vehicle wouldbecome 30 uncontrollable if any of the drag link or tie rod connectionsshould become disconnected.

Other and further important objects of this invention will be apparentfrom the disclosures in the specification and the accompanying drawingThis invention (in a preferred form) is illustrated in the drawings andhereinafter more fully described.

011 the drawings:

Figure 1 is a vertical cross section of a ball joint embodying thefeatures of this invention.

Figure 2 is a section on the line II-II of Fi ure 1.

igure 3 is an end elevation of a modified form of the device.

Figure 4 is a side elevation of the modified form of Figure 3 partly insection disclosing a modified form of connection to the tie rod proper.

Figure 5 is a disassembled view of one ball seat with the spring andplug.

As shown on the drawings:

A tie rod has been chosen for illustration, its end being threaded at 11to adjustably receive the corresponding internally threaded extension 12of the socket member or shell 13. After this adjustment has been made,which governs the toe-in of the steering wheels, a jam nut-'14 with aconical surface slightly gs side clearance for the stem. A secondaperside of the ball 19 1927. Serial No. 182,885.

is screwed up against the correspondingly tapered end of the extension12 to ti htly wedge the extension onto the tie rod, as s own 1n F1gure2. As an alternative procedure, the extension 12 ma be split and flangedas at 15 in Figure 4 an a bolt 16 used to clamp the extension onto thetie rod to preserve the adjustment.

he socket member or shell 13 forms an enlarged cylindrical continuationof the extention 12 and an aperture 17 is provided in the top for thestem 18 of a spherical ball 19, the aperture 17 being too small topermit passage of the ball 19, but providing a'limited ture 20 isprovided in the bottom of the shell 13 offset to the left of the axis ofthe first aperture, this second aperture being large enough to. permitthe passage of the ball 19, the lower aperture being offset to provideroom for the insertion of the ball when the inner ball seat is in place.As it is desirable, but not essential, to have the outer edges of theseapertures form a plane surface to simplify the form of closures thereforthe shell is drawn out into cylindrical bosses 21 and 22 around eachaperture, as indicated in the elevational views.

The lower aperture 20 is permanently sealed bya cover 23 after the balland bearings have been assembled inthe shell, this cover beingpreferably of an initial convex form which is sprung into place as afiat disk. 4

The cylindrical shell 13, forms a housing for two ball seats 24', onedisposed on either these seats being of substantially disk-like formwith spherically formed depressions 25 in one face to bear against theball 19.

It will be evident that the inner ball seat, which seats against-ashoulder 26 provided by theextension 12, is held in place by the ball 19when once assembled. The outer ball seat is resiliently urged againstthe ball by a helical spring 27 backed by a plug 28 screwed into theopen end of the shell 13 and held by a cotter pin 29, the plug beingscrewed in until it takes up practically the entire movementof thespring, as shown in Figure .2, in order that spring failure can onlyresult in a sli ht loosening up of the connection as a whofe. As wearoccurs on the ball or ball seats this spring tends to take up any lostmotion pro uce by such wear, thus preventa in-g rattling. Even thoughthe plu 28, spring 27, and the outer ball seat s ould drop out theconnection between the ball 19 and the shell 13 is maintained as theaperture 17 is too small to permit the withdrawal'oi the balltherethrough.

In assembling the parts one of the ball seats 24 is inserted against theshoulder 26 and the ball 19 and stem 18 inserted throu h the a erture20, which is then permanent y 1 sealed by a sprung in cover 23 so thatthereafter the ball is not removable.- The outer ball seatis theninserted backed by the sprin 27 and plug 28 which is removably secure bythe cotter pin 29in order that these arts may be removed for inspectionand a justment.

It willthus be seen that I have provided an improved form of ball jointhaving the advantages of simplicity and extreme safety accompanied byeconomy of production and ease of inspection and adjustment tocompensate for wear.

I am aware that many changes may be made, and numerous details ofconstruction :0 may be varied through a wide range without departingfrom the principles of this invention, and I therefore do not purposelimiting the patent'granted hereon, otherwise than necessitated by theprior art.

85 I claim as my invention:

A ball joint coupling adapted to engage a spherical ball on the end of astem comprising a cylindrical shell open at one end, said shell havingoppositely disposed apertures 40 having flanges therearound formingplane surfaces, one aperture being of a size suitable for the insertionof a ball stem while the other is of a larger size suitable to permitthe insertion of the ball therethrough, a per- 46 manent seal for saidsecond larger aperture,

a reduced extension of said shell opposite the open end for attachmentto the end of a tie rod, said reduced extension forming a shoulder, aball seat positioned between the 50 shoulder and the ball, a second ballseat engaging said ball diametrically opposite to said first mentionedball seat, and means for retaining said second ball seat in position.

In testimony whereof I have hereunto subscribed my name at Detroit,Wayne County,

Michigan. 1

FREDERICK C. CRAW'FORD.

